The present invention relates to a coating method which coats a coating liquid or a coating solution onto a conveyed base member to be coated and to a coating system.
Heretofore, in order to conduct a coating preparation operation while a coating liquid is flowed out when the coating liquid is coated onto a conveyed base member by means of a coater (for example, in the case of a slide hopper coater, in order to conduct equalization of the slit outlet port in such a manner that the coating liquid is uniformly coated from slit of coater 8 and cleaning of the drop of excessive coating liquid from lip of coater 8 while flowing out the coating liquid), prior to coating the coating liquid onto the base member, the coating liquid is caused to flow out from the coater without coating the coating liquid onto the base member. Therefore, during conducting the coating preparation operation while flowing out the coating liquid from the coater, the coating liquid continues to flow out from the coater. After the coating preparation operation is finished, the base member is conveyed. When the coating starting point of the base member reaches the coater, coating of the coating liquid onto the base member starts.
Heretofore, the flow rate of the coating liquid while conducting the coating preparation operation and until the coating starting point of the base member reaches the coater was the same as coating flow rate.
The coating liquid flowing out during conducting the coating preparation operation is finally discarded. Since the feeding flow rate of the coating liquid while conducting the coating preparation operation was the same as the coating flow rate, there was a problem that loss of expensive coating liquid became large.
The leading portion of the base member is ordinarily a leader for feeding an area of the base member in which the coating liquid is coated at the coating flow rate along with a conveyance path. It is not ordinarily coated. Accordingly, the coating liquid fed until the coating starting point of the above-mentioned base member reaches the coater becomes loss. If the coating liquid is fed to the coater at the same feeding flow rate as the coating flow rate, loss of expensive coating liquid is further increased.
Therefore, if feeding of the coating liquid is stopped since the coating preparation operation is conducted until the coating starting point of the base member reaches the coater in order to prevent increase of the loss of the coating liquid, excessive drop occurs on the lip of the coater or the coating liquid cannot be fed from the slit of the coater. Therefore, feeding of the coating liquid cannot be stopped until the coating starting point of the base member reaches the coater.